Set a MNE-Python preference key in the config file and environment.
strThe preference key to set.
str | NoneThe value to assign to the preference key. If None, the key is deleted.
str | NoneThe folder that contains the .mne config folder. If None, it is found automatically.
If True (default), update os.environ in addition to
updating the MNE-Python config file.
See also
mne.set_config#